Electrical switch



B. D. HORTON.

ELECTRICAL SWITCH.

APPLICATION n'ugu JULYIH. 191s.

* Patented July 1, 1919.

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BRYSON DEXTER HORTON OF DETROIT, MICHIGAN.

ELECTRICAL SWITCH.

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- Specification of Letters Patent.

Patented July t, lain.

Application filed July 13, 1916. berial No. 108,984.

T 0 all whom it may concern Be it known that T, BRYSON DEXTER Hon- TON, a citizen of the United States, residing in the city of Detroit, county of Wayne, and

State of Michigan, have invented certain new and useful Improvements in Electrical Switches, of whlch the following, taken in .connection with the accompanying sheet of lltll b scription.

My present invention more particularly relates to switch mechanism in whlch three drawin s, is a full, clear, and concise deor more'spaced apart pairs of cooperating llti til

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contacts are provided. It has for one of its objects the provision of means for operating the movable contacts by the application of a balanced power or force in such a way as to separate all the contacts simultaneously, and which will prevent anyltwistin or distortion of the parts of the switch. he type of switch to which my present invention is particularly applicable is that of the knife blade type having-three or more blades or movable contacts connected by a bar or cross-head, whereby the "said contacts may be simultaneously moved. To operate this cross-head an operating crank is provided, which operating crank, in the illustrated em bodiment of the invention, is shown mounted in opposite sides of an inclosing housing. The operating crank and cross-head are operably associated in such a way that the force or power for opening or closin the switch is applied so as to freely and s1multaneously break or make the connection without twisting the knife-blades about their pivots or racking the connections between the blades and the cross-head. To accomplish this ll provide connecting devices-fats tened to or carried bythe crank and connected to the crosshead intermediate of the points of its connection with the contacts, so that upon the operating of the cranlt the power is applied in a .most advantageous manner without objectionable stresses being transmitted to any of the switch parts.

A further object of my invention is to provide a cheap and simplified construction of cross-head and knife-blade connecting means, a simplified form of connection between the cross-head and the operating crank and other noveldetails of construction which will manifest themselves-upon a reading of the following specification.

Referring to the drawings, in which it have shown one preferred form of switch mechanism embodying the principles of my invention;

Figure 1 is a top plan view of a switch mechanism of the inclosed type embodying thenovel features of my invention.

Fig. 2 is a view in sectional side elevation and taken on line A-A of Fig. 1.

The switch illustrated is of the three pole double throw type, comprising two series of stationary contacts 1 of the jaw type, and a series of coiiperating contacts 2 of the knifeblade type, the latter being pivoted at 2' in.- termediate of the two series of'j aw contacts and equally spaced therefrom, so that an electrical connection with either series can be had as desired.

The knife blade contacts 2 are connected by a cross-head 3 of rectangular outline and preferably of insulating material. The con nection between the cross-head and the'knifeblade contacts is shown more clearly inFig. 2, where it will be noted that the ends of the knife-blade contacts terminate in reduced portions 4: that are received in openings that are provided therefor in thecross-head. it will be observed that the cross-head being connected to the knife-blade contacts at or near the ends of the latter ives better support to the blades and maintains them in perfectalinement. To make the operative connection permanent, a washer 5, having a rectangular opening which will freely receive the end of the projection a, is mounted upon said end and against the cross-head and then theend of the reduced portion is riveted overat 6 so as to firmly retain the washer and cross-head in assembled relation to the knifeblade contacts. The switch con acts are mounted upon a porcelain or other insulating base 7, secured to the bottom of the metallic housing 8.

it will be observed thatthe contacts both stationary and movable are spaced apart preferably at an equal distance from each other and the movable contacts will, by reason of their inter-connection through the" medium of the cross-head, be simultaneously operated.

In order to operate the movable contacts,

an operating crank or member 9 is provided,

llllli casing at points 10 and 11, substantially in axial alinement with the pivot points 2 of the movable contacts, so that substantial throw or movement of the switch may be had. .1 he crank 9 and the cross-head 3 are connected by means of connecting members 12, these being preferably positioned between the spaced apart knife blade contacts so that upon the operation of the crank the forceapplied to open or close the switch will be transmitted in an equalizing way to the mov ingparts to insure perfect alinement and prevent objectionable racking or distortion thereof.

One form of connecting member 12 is illustrated preferably so on account of its simplified character and' cheapness of construction. This connecting member takes the form of a sheet metal U-shaped strap which partly encircles the crank at 12, and having its ends or extremities 14 positioned in contact with opposite sides of the rectangular cross-head 3, these ends being secured to the cross-headby means of the threaded bolt 15 and cooperating nut 16. Of course, other forms of connecting members for operably associating the crank with the cross-head may be used if found desirable.

It will furthermore be observed that in a doublethrow switch of the character illustrated the relative position of the operating? crank with respect to the ends of the knifeblades and the mounting and the connecting of the crosshead with the operating crank add symmetry to the whole and at the same time the parts are balanced to effect a satisfactory application of operating power.

While I have illustrated and described one specific embodiment of my invention, 1 do not wish to be understood as limiting myself to the described details of construction and arrangement of parts as these may be changed or altered without departing from the spirit and scope of my invention as defined by the following claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. An electrical switch provided with a plurality of independent knife blades, each blade being independently pivotally mounted at one end, a cross head connecting the blades at the other end and forming the sole connection therebetween, an operating member provided with a portion extending parallel to said cross head and a strap member passing around the said parallel portion of the operating member and having its ends fastened on opposite sides of the cross head.-

2. An electrical switch provided with a plurality of independent knife blades, each blade being independently pivotally mounted at one end, a cross head connecting the blades at the other end and forming the sole connection therebetween, an operating member provided with a portion extending parallelto said cross head, and a strap member passing around the said parallel portion of the operating member and having its ends fastened on opposite sides of the cross head by meansof a single fastener engaging both ends of the strap member.

BRYSON DEXTER HORTON. 

